A new software utility called XperiFirm has been created allowing you to download Sony Xperia firmware for all devices. XperiFirm is a very useful tool, giving you the choice to download firmware from any region for your particular Xperia handset i.e. this is a great alternative to changing your build.prop.
What XperiFirm does is scour Sony’s servers for the latest firmware – the software will only show you what exists on Sony Mobile’s servers. Once you have chosen the CDA to download, it will then download the official FILE_* files that FlashTool can decrypt and bundle to create a FTF firmware file (“Tools” > “Bundle Creation”, within FlashTool).
All props go to IaguCool from XDA for a very useful piece of software. To give XperiFirm a try you will also need to be running Java Runtime Environment and Microsoft .NET Framework 2.0 or newer. The download file can be found below.
Thanks Davide, Mirhawk, and Ruben!